1. Field of the Invention
The present invention relates to a method for manufacturing a thin film transistor array panel, and more particularly to a method for manufacturing a thin film transistor array panel including a plastic substrate.
2. Description of the Related Art
A liquid crystal display (LCD) and an organic light emitting display (OLED) are common types of flat panel displays.
An LCD includes two panels provided with field-generating electrodes such as pixel electrodes and a common electrode and polarizers, and a liquid crystal (LC) layer arranged therebetween. Voltages are applied to the field-generating electrodes to generate an electric field in the LC layer. The electric field determines orientations of LC molecules in the LC layer to adjust polarization of incident light for displaying an image.
An organic light emitting display (OLED) is a self-emissive display device, which displays images by exciting an emissive organic material to emit light. The OLED includes an anode (hole injection electrode), a cathode (electron injection electrode), and an organic light emission layer arranged therebetween. When holes and electrons are injected into the light emission layer, they are recombined and annihilated while emitting light.
However, because the liquid crystal display and the organic light emitting display include a fragile and relatively heavy glass substrate, they are not suitable for portable and large scale displays.
Accordingly, a display device using a flexible substrate such as plastic, which is relatively light and strong, is being used.
When the plastic substrate is used instead of the glass substrate, the LCD is more portable, stable, and has a lighter weight. A deposition process and a printing process may be used to form the flexile display, and the flexible display using the plastic substrate may be manufactured by a roll-to-roll process. Accordingly, mass production is possible, which reduces production cost.
However, problems arise because the plastic substrate expands during the manufacturing process due to the high temperature since a weak heat resistant property of the plastic substrate results in a misalignment of the thin film patterns.